Как думаете, для чего этот запрос?

Собственно:

SELECT  COUNT(*) FROM _ReferenceChngR611
DELETE FROM _ReferenceChngR611 WHERE _NodeRRef IN (SELECT _IDRRef FROM _Node6 WHERE _Fld2424 = 1)
DELETE FROM _InfoRgChngR2057 WHERE _NodeRRef IN (SELECT _IDRRef FROM _Node6 WHERE _Fld2424 = 1)
DELETE FROM _InfoRgChngR1495 WHERE _NodeRRef IN (SELECT _IDRRef FROM _Node6 WHERE _Fld2424 = 1)
DELETE FROM _InfoRgChngR1611 WHERE _NodeRRef IN (SELECT _IDRRef FROM _Node6 WHERE _Fld2424 = 1)
DELETE FROM _InfoRgChngR1791 WHERE _NodeRRef IN (SELECT _IDRRef FROM _Node6 WHERE _Fld2424 = 1)
DELETE FROM _InfoRgChngR1569 WHERE _NodeRRef IN (SELECT _IDRRef FROM _Node6 WHERE _Fld2424 = 1)
DELETE FROM _InfoRgChngR2716 WHERE _NodeRRef IN (SELECT _IDRRef FROM _Node6 WHERE _Fld2424 = 1)
DELETE FROM _InfoRgChng2624   WHERE _NodeRRef IN (SELECT _IDRRef FROM _Node6 WHERE _Fld2424 = 1)
DELETE FROM _InfoRgChngR1753 WHERE _NodeRRef IN (SELECT _IDRRef FROM _Node6 WHERE _Fld2424 = 1)
DELETE FROM _DocumentChngR1295 WHERE _NodeRRef IN (SELECT _IDRRef FROM _Node6 WHERE _Fld2424 = 1)
DELETE FROM _AccumRgChngR1815 WHERE _NodeRRef IN (SELECT _IDRRef FROM _Node6 WHERE _Fld2424 = 1)
DELETE FROM _ReferenceChngR246 WHERE _NodeRRef IN (SELECT _IDRRef FROM _Node6 WHERE _Fld2424 = 1)
DELETE FROM _ReferenceChngR2812 WHERE _NodeRRef IN (SELECT _IDRRef FROM _Node6 WHERE _Fld2424 = 1)
DELETE FROM _ReferenceChngR592 WHERE _NodeRRef IN (SELECT _IDRRef FROM _Node6 WHERE _Fld2424 = 1)
SELECT  COUNT(*) FROM _ReferenceChngR611